Integrated circuits such as processors, memory devices, memory controllers, input/output (I/O) controllers, and the like typically communicate with each other using digital data signals and clock signals. Some systems use high speed serial or parallel data links such Peripheral Component Interconnect (PCI) links, PCI-Express links, parallel Advanced Technology Attached (ATA) links, serial ATA links or the like.
Circuits that implement high speed serial or parallel data links may operate in different states. For example, if a driver circuit is not in use, it may transition from a fully operational state to a reduced power state. Transitioning back from a reduced power state to a fully operational state may take a varying amount of time, depending at least in part on the circuit topology of bias circuits that provide bias currents and/or bias voltages to the driver circuit.